1. Field of the Invention
The present invention relates to an inverted microscope which generates an observation image of a sample by using an objective lens placed under the sample.
2. Description of the Related Art
Conventionally, an inverted microscope has been widely used for an observation of a sample such as a cell soaked in a culture fluid (cultured cell). In such an observation, a container such as a Petri dish filled with the culture fluid is mounted on a stage, and an objective lens provided under the sample is used to generate an observation image. In a case of performing a time-course observation of a cultured cell for example, it is necessary to replace the culture fluid. On this occasion, there is a problem that the culture fluid is spilled out of the container by mistake on the stage and the spilt fluid intrudes in a main body of the microscope, resulting in polluting an optical member and a mechanism member provided in the main body of the microscope and damaging the function thereof.
In response to this problem, techniques disclosed in Japanese Patent Application Laid-Open No. 2002-90645, Japanese Utility Model Application Laid-Open No. H5-50413, and Japanese Patent Application Laid-Open No. 2006-162770 have been proposed. In an inverted microscope disclosed in the Japanese Patent Application Laid-Open No. 2002-90645, a waterproof sheet which has a hole for securing a path of an observation light at its center is provided over a main body of the microscope. In a state that a vertical motion board which moves an objective lens in the vertical direction is fitted in the hole at the center, a vicinity of circumferential edge part of the hole is settled on the vertical motion board with a rubber band. With this structure, the fluid spilled from the sample and the like is retained on the waterproof sheet or induced to flow down to an outward through the waterproof sheet. Thus, an intrusion of fluid into the main body of the microscope is prevented.
In an inverted microscope disclosed in Japanese Utility Model Application Laid-Open No. H5-50413, a water receiver having a tray shape is provided to a part, located within a main body of the microscope, of a vertical motion unit which moves an objective lens in the vertical direction. Therefore, the fluid which has intruded from a gap between an upper wall surface of the microscope main body and the vertical motion unit protruding from the upper wall surface is received by the water receiver. A discharge path is connected to the water receiver and the fluid received by the water receiver is discharged to an outward through the discharge path. Hence, a pollution caused by fluid is prevented because the fluid having intruded into the microscope main body is discharged before reaching an optical member and a mechanism member.
In an inverted microscope disclosed in Japanese Patent Application Laid-Open No. 2006-162770, a tray which is used for receiving water and has a size larger than a stage is provided between the stage and a main body of the microscope. Therefore, the fluid spilled from the sample and the like is received by this tray. Because the fluid is controlled not to be spilled onto the microscope main body in this manner, an intrusion of fluid into the microscope main body is prevented.